Medium Format, Why On Earth?

When photography just started, and a bright idea of an optical enlarger was not born yet, a size of a photograph was determined by the size of a light-sensitive plate used and, consequently, by the size of a camera capable of accommodating that plate. That is why cameras of the distant past were so impressively huge. Today cameras of this type are referred to as “view cameras”, or simply “large format”. Later, when Lumier brothers invented cinema, photographers realized that the same principle of image projection could be used to create prints of any size.

The first camera based on this idea was Kodak Brownie (Fig. 1). It used so-called 120 roll film, which was 60mm (2 1/4”) wide and had a frame size 6×9 centimeters. Brownie truly democratized photography making it affordable and relatively easy to use. However, it was still bulky and cumbersome.

Fig. 1 Kodak Brownie, the first portable camera

Oscar Barnack was the first one who managed to successfully squeeze a picture into an even smaller frame of 24x36mm by creating a camera that used ciné film, yet had a frame size twice of that of a standard movie camera (Fig. 2). Since then, photography has never been the same: it became mobile, unobtrusive and much less staged than it used to be in times of view cameras with wooden tripods and bellows larger than of an accordion. Was it also smaller than the Brownie, which had a size of almost a shoe box. So, 35mm became “Small Format”, or “35mm”, while Brownie and other cameras using 120 (and later 220) film became “Medium Format”.

Fig. 2 The first successful 35mm camera “Ur Leica” circa 1901

Then… It just so happened that prints made from 120 roll film looked somehow better. Primarily it was due to a simple fact that the film of the same speed (i.e. ISO rating) looked the more grainy, the more it was enlarged. Since the larger frame needed less enlargement for the same size print, the result looked less grainy. Moreover, a larger negative area could hold more detail, which meant higher resolution prints.

Another problem with 35mm format was that it had to be more high-tech to achieve results comparable to medium format. Higher degree of enlargement required more precision and higher tolerances in production of camera parts and especially lenses. Even when using the finest grain film, a lens with the same resolution as its medium format counterpart would produce results less sharp on a print of the same size. Therefore 35mm format lenses had to have higher resolution. It was possible only with use of more expensive types of glass and the highest-precision grinding techniques and other expensive technologies. All that made 35mm cameras harder and more expensive to manufacture, and it is the photographers that had to pay the price. It continued to be the case until Japanese camera makers set out to make 35mm format accessible to everyone. Their Canon and Nikon rangefinder cameras and later SLRs flooded the market, and the prices indeed went down for most camera makes. Leica and Contax (the Carl Zeiss brand), though, were still of substantially higher quality, hence commanded premium prices. By mid 1960-s most amateur photographers moved to 35mm cameras. Obvious convenience of 35mm format, however, was not enough to satisfy professional photographers, especially studio and wedding shooters, who needed better image quality to be able to print larger. Photo gear manufacturers kept producing medium format cameras in smaller numbers, which drove prices up, and the situation on the market flipped. Another contributing factor was making medium format cameras much more technologically advanced, both in terms of manufacturing tolerances and electronic features like AF, flash metering, etc. Now medium format equipment costs thousands of dollars more than 35mm (Fig. 3).

Fig. 3 Leica S007, Leica Summarit-S 2.4/70 CS with leaf shutter

Film industry was working hard to improve image quality on their side. They kept introducing more and more fine-grained and high-speed film. By early 1990-s, the quality of color slide film, namely Fuji Provia 100F and 400F was so high that grain seized to be a determining factor in image quality. New 35mm-format lenses and digital image capturing technology (scanners) were so good that 35mm cameras became rivals to medium format in consumer print sizes in terms of sharpness and resolution. Modern 35mm film has the native resolution of 24 megapixels, which incidentally roughly equals effective resolution of the human eye (things are a little bit more complex on the retina, but let’s not go there). Modern 35mm sensors surpass that as much as two-fold seemingly making medium format obsolete. However…

Fig. 4 Leica S006, Carl Zeiss Sonnar 2.8/140 T*

If you take a picture of the same subject matter with a 35mm and medium format cameras, enlarge both photos to the size that does not push any of the two to their limits, somehow, the photo taken with the medium format camera will “look more alive” to a substantial part of the audience (Fig 4). Interestingly, if you ask people who see this difference what is the reason for it, most of the will have a very hard time explaining. This is because this difference is perceptual rather then quantifiable. It is, however, so noticeable that commercial photographers still invest in medium format gear, even though the prices, especially for premium brands like Hasselblad and Leica, as well as super-high-resolution Phase One digital backs, are nothing but astronomical.

Fig. 5 Leica S006, Carl Zeiss Planar 2/80 T”

So, what does make it so lifelike? Medium format pictures seem to look more 3D, have more depth. The reason for that is higher micro-contrast of medium format optics. Micro-contrast of a lens, not to be confused with overall contrast of the scene, it is the lens’ ability to resolve close tonal variations of small adjacent areas of the same color palette. The thing about micro-contrast, as an optical property of the lens, is that it is in direct conflict with the resolving power, or measurable sharpness. Medium format optics circumvents this conflict, as it does not need as high of resolving power as 35mm format lenses do. By projecting the visual information onto a larger area, it just does not have to resolve as much. This fact gives optical engineers a luxury of constructing lenses with higher micro-contrast. While 35mm lenses that have high micro-contrast and are reasonably sharp at the same time do exist (for instance, Leica and Carl Zeiss optics of classic designs), most of them are no less expensive than the medium format glass.

Medium format comes at a serious cost, which is not just monetary: Both cameras and lenses are substantially larger and heavier than comparable 35mm gear. Even the newest mirrorless cameras Hasselblad X1D and Fuji GFX50, while have relatively compact and light bodies, still need lenses that turn a concept of “light and portable medium format” into an oxymoron. Medium format requires longer focal lengths, and it places restriction on handholding exposures, unless you use studio flashes (we all know that using an on-camera flash almost never results in pictures that have even a slimmest potential of being sold). Shallower depth of field at any aperture is yet another a reason to use a tripod.

Fig. 6 Leica S006, Carl Zeiss Sonnar 2.8/140 T*

Now, another seemingly peculiar fact: even without looking at MTF charts, it is quite clear that medium format lenses have much more modest specifications than their 35mm counterparts. For instance, there is not a single medium format lens with the maximum aperture of f/1.4. In fact, f/2 is considered super fast and exotic. Medium format zooms are usually no faster than f/4 and have a shorter focal length range. Sensors of medium format cameras, except for the most advanced ones like Leica S007, are noisier than 35mm ones. Why? Not only because everything is harder on a larger scale, but also because there is no need: while on a pixel level the image may look much less clean as a file from Sony a7R II, when it comes to the final product, the print will look better.

Fig. 7 Contax 645, Carl Zeiss Distagon 3.5/55 T*, Phase One P25

That being said, there is a real reason medium format still exists. The only camera and lens brand that truly rivals medium format is Leica M, yet, when it comes to Leica and Carl Zeiss medium format lines, there is no contest. All things being equal, the medium format photos just look better, and this is not going to change, because laws of physics will not allow it.